ScienceShot

Grizzly bear 'highway' discovered in Canada

Grizzly bears and humans along the Pacific coast of North America have shared a hunger for salmon for millennia. The fish figure prominently in many Canadian coastal First Nations’ cultures, including that of the Heiltsuk, who settled in the Great Bear Rainforest of British Columbia more than 9000 years ago—and have lived alongside the grizzly bears since then. Wildlife biologists have also tied the rise and fall of grizzly bear numbers to salmon abundance. Now, by means of an unusual collaboration of Heiltsuk Nation members and scientists, researchers report finding a new aggregation of the salmon-feeding bears—many of whom (such as the one in the photo above) journey hundreds of miles along a route so well-traveled, the team likens it to a highway. In 2009, after establishing the Koeye River Conservancy, a protected area in the rainforest, the Heiltsuk joined with the scientists to find out how the ursines and salmon were faring. Over 3 years, they counted the fish and conducted a noninvasive DNA survey of the bears by collecting bits of the animals’ fur as they walked by scented wire snares during the salmon-spawning season. Genetic analysis of the samples identified nearly 60 individual bears that depend on the salmon, the team reports in the current issue of Ecology and Society. But the survey also indicated that the bears’ numbers are decreasing, which the scientists say is likely tied to lower numbers of salmon, which may have led to hungry grizzlies seeking human food and getting shot, as well as to trophy hunting of the male animals when they traveled outside the conservancy.